> This implements hardware performance events for the EV67 and later> CPUs within the Linux performance events subsystem. Only using the> performance monitoring unit in HP/Compaq's so called "Aggregrate> mode" is supported.> > The code has been implemented in a manner that makes extension to> other older Alpha CPUs relatively straightforward should some mug> wish to indulge his or herself.

Below is the incremental diff.

I have a note here that Peter had issues with the earlier version ofthis patch. But I see no info here regarding what those issues were,nor whether or how they were addressed.

- /* la_ptr is the counter that overflowed. */+ /* Completely counting through the PMC's period to trigger a new PMC+ * overflow interrupt while in this interrupt routine is utterly+ * disastrous! The EV6 and EV67 counters are sufficiently large to+ * prevent this but to be really sure disable the PMCs.+ */+ wrperfmon(PERFMON_CMD_DISABLE, cpuc->idx_mask);